Las Cruces has a desert climate . Winters alternate between colder and windier weather following trough and frontal passages, and warmer, sunnier periods; light freezes occur 69 nights on average. Spring months can be windy, particularly in the afternoons, sometimes causing periods of blowing dust and short-lived dust storms. Summers begin with the hottest weather of the year, with some extended periods of over 100 °F or 37.8 °C weather not uncommon, while the latter half of the summer seeing increased humidity and frequent afternoon thunderstorms, with slightly lower daytime temperatures. Autumns feature decreasing temperatures and precipitation.
Precipitation is very light from October to June, with only occasional winter storm systems bringing steady precipitation to the Las Cruces area. Most winter moisture is in the form of rain, though some light snow falls most winters, usually enough to accumulate and stay on the ground for a few hours, at most. Warm season precipitation is often from heavy showers, especially from the late summer monsoon weather pattern.
Since records began in 1892, the lowest temperature recorded at State University has been −10 °F or −23.3 °C on January 11, 1962 – though only ten nights have ever fallen to or below 0 °F or −17.8 °C – and the highest 110 °F or 43.3 °C on June 28, 1994. The lowest maximum on record is 16 °F or −8.9 °C on January 28, 1948 and the highest minimum 80 °F or 26.7 °C on July 5, 1920. The wettest calendar year has been 1941 with 19.60 inches or 497.8 millimetres, although 1905 with 17.09 inches or 434.1 millimetres is the only other year to exceed 15 inches (380 mm). The only months to exceed 6 inches (150 mm) have been September 1941 with 7.53 inches or 191.3 millimetres and August 1935 with 7.41 inches or 188.2 millimetres. The wettest single day has been August 30, 1935 with 6.49 inches or 164.8 millimetres and the driest calendar year 1970 with 3.44 inches or 87.4 millimetres.